The Sydney Morning Herald's Economics Editor

Would you be surprised if I told you the resources boom and its two-speed economy had led to a big increase in the number of people shifting between states? No, I thought not.

Well here's my surprise: it hasn't gone up, it has gone down. Research by Professor Jeff Borland, of the University of Melbourne, finds that the rate of interstate migration has declined over the past decade.

The eternal lament of oldies (me included) is that we're getting more and more like America. But this is one respect in which we aren't. The Americans are inveterate movers between states, but we have never moved as much as they do, and now even fewer of us are doing it.

''Australians have never been big movers,'' Borland says. ''Most of us complete our schooling in the same state. We're not likely to shift states to find employment if we lose our jobs. And when we move in retirement, this is mostly to another place in the same state.''

Borland's paper shows that, in 2003, the proportion of the population moving between states was 2.1 per cent. Last year it was just 1.5 per cent, a decline equivalent these days to 130,000 fewer people.

This was the lowest rate for at least 40 years. And it was no flash in the pan. It was the continuation of a decline that's been occurring steadily for 10 years. The rate of interstate migration rose between the mid-'70s and the late-'80s, then stayed pretty stable at about 2 per cent a year until the early noughties.

The rate of decline was reasonably similar in all states, with one exception. No, it wasn't Western Australia. It was Queensland. And Queensland's share of the decline wasn't disproportionately smaller than for the other states, it was larger.

The decline has occurred among people of all ages. But that's not to say people of all ages are equally likely to pack up and move interstate. They aren't.

Borland finds that the peak ages for state migration are the 20s and 30s. ''People above 40 years move progressively less as they get older,'' he says.

If we take the example of the late 1990s, one in 25 people aged 20 to 24 moved interstate in the previous year, whereas for those aged 70 to 74 it was one in 200.

So why has interstate migration declined? If moving tends to be concentrated among people in their 20s and 30s, could such migration be down because, with the ageing of the population, people in that age range now constitute a smaller proportion of the total population?

No, the overall decline is explained by declines in all age groups, although it's true that the decrease has been larger at younger ages.

It seems clear to me that most interstate migration is work-related. Or, as Borland puts it, ''suppose we think of the main rationale for interstate migration as being to match the location of the population to the location of jobs''.

In that case, could the decline in movement between states be caused by less reallocation of jobs between states? Doesn't seem so. An index of the annual change in the distribution of employment by state shows no downward trend in the extent of change.

So what is the reason? Borland isn't certain, but he finds evidence to support the idea that the change is in the behaviour of recent immigrants to Australia, not that of people long resident here. There's been an increase in the correlation between the states immigrants first come to and the states where employment is growing fastest.

My guess is it gets back to the Howard government's move to a much greater proportion of skilled migration, with greater employer nomination of migrants via 457 visas. Migrants are now more likely to come straight to a particular job than to land in Sydney or Melbourne and start hunting for one somewhere in Oz.

Rivalry between the Coalition and Labor can reach petty levels. The budget papers always had white covers until the Rudd government decided dark blue would be a good reform. Under the Abbott government they've reverted to white.

For many years the federal government spelt ''program'' the way this newspaper does. But John Howard, spiritual son of Bob Menzies, insisted it revert to the fancy English spelling. Labor changed it back to the no-bulldust way. Now Tony Abbott, spiritual son of Howard, has reverted to ''programme''.

Pedants who know their stuff know the Poms - including Shakespeare in his day - used the simple spelling until the 19th century, when it was prettied-up during a bout of francophilia.